| 摘要 |
1527780 Ceramic formed body MAXPLANCK-GES ZUR FORDERUNG DER WISSENSCHAFTEN EV 4 Nov 1976 [5 Nov 1975] 45920/76 Heading C1J A ceramic formed body of fracture toughness up to 10 MN/m<SP>3/2</SP> comprises a ceramic matrix and at least one phase dispersed therein of ceramic incorporation material, this material being present at the production temperature of the ceramic body and at ambient temperature in different enantiotropic solid modifications, the densities of which are different by more than 3% and the ceramic body being permeated by micro-cracks with a size of 1 Ám. or less in a density of 10<SP>6</SP> to 10<SP>7</SP>/mm<SP>3</SP>. Preferably the matrix consists of aluminium oxide or magnesium oxide and the incorporation material consists of non-stabilized zirconium dioxide (4-25 vol. per cent) or hafnium dioxide, carbide or nitride. In addition, the ceramic body may contain an embedded phase which consists of a ceramic matrix and at least one phase dispersed therein of ceramic incorporation material but having a content of incorporation material which differs from that of the base material. Also the ceramic body may consist of at least two layers with a different content of ceramic incorporation material. |
